1 Small molecules are used as the basic units in the synthesis of large food molecules. Which statement is correct? A Amino acids are basic units of carbohydrates. B Fatty acids are basic units of glycogen. C Glycerol is a basic unit of oils. D Simple sugar is a basic unit of protein. 2 When a substance is added to meat, amino acids are produced. What is this substance? A a hormone B an enzyme C an oil D water 3 The diagram shows part of a protein molecule. X What does X represent? A amino acid B fatty acid C glycerol D sugar PhysicsAndMathsTutor.com 4 Four different foods were tested for their composition. The results are shown in the table. Which food contains protein but not reducing sugar or starch? Benedict’s test iodine test biuret test A blue black purple B blue lue brown purple C brick red black blue D brick red brown blue 5 What are the smaller basic units of starch and glycogen molecules? starch glycogen A amino acids fatty acids and glycerol B amino acids simple sugars C simple sugars fatty acids and glycerol D simple sugars simple sugars 6 The diagram represents a protein molecule. What do the small circles represent? A amino acids B fatty acids C glycerol D simple sugars PhysicsAndMathsTutor.com 7 Which row shows the elements and basic units that are used in the construction of large food molecules? food molecules elements basic units A fats carbon, hydrogen, oxygen, nitrogen glucose B fats carbon, hydrogen, oxygen, nitrogen glycerol C starch carbon, hydrogen, oxygen glucose D starch carbon, hydrogen, oxygen glycerol 8 Which nutrient produces a purple colour when mixed with biuret solution? A fat B protein C reducing sugar D starch 9 Which simple molecules are the basic units of protein? A amino acids B fatty acids C sugars D vitamins 10 Which food-testing reagent shows a positive result when it turns from blue to purple? A Benedict’s solution B biuret reagent C ethanol D iodine solution PhysicsAndMathsTutor.com 11 The diagram shows two food tests carried out on solution X. test 1 test 2 Benedict’s solution biuret solution red colour heat solution X purple colour solution X Which nutrients are present in solution X? A protein and starch B protein and sugar C starch and fat D starch and sugar 12 The data show the concentrations of sugar and starch in an onion. total sugar including reducing sugar / g per 100g 3.7 . starch / g per 100g 0. The onion is tested with Benedict’s solution and iodine solution. Which set of results is correct? Benedict’s solution iodine solution A blue lue blue-black B lue blue brown C brick red blue-black D brick red brown PhysicsAndMathsTutor.com 13 The diagram shows two food molecules before and after they have been digested by enzymes. R P Q S before after What identifies the products of fat digestion? A P and R B P and S C Q and R 14 Four foods were tested for each of the following nutrients: fat (using ethanol); protein (using the biuret test); reducing sugar (using Benedict’s solution), Which food contains protein and fat? PhysicsAndMathsTutor.com D Q and S 15 The graphs show the quantities of selected vitamins and mineral ions in four foods. vitamin D µg per 100 g iron mg per 100 g calcium mg per 100 g 150 20 10 2 100 10 5 1 50 0 0 0 0 beans egg fish fruit 3 beans egg fish fruit 15 beans egg fish fruit 30 beans egg fish fruit vitamin C mg per 100 g Which food is the richest source of the vitamin or mineral ions essential for the transport of oxygen by the blood? A beans B egg C fish D fruit 16 A human cell contains a length of DNA that carries the code for making which substance? A fat B glycogen C lipase D starch 17 A student set up a test-tube containing starch, water and amylase. How could the student test whether the amylase had digested all the starch? A Add Biuret solution. B Add dilute hydrochloric acid. C Add iodine solution. D Weigh the test-tubes and contents before and after the experiment. PhysicsAndMathsTutor.com 18 When solution X is tested with iodine solution, a blue-black colour is observed. A different solution, Y, is added to a new sample of solution X and the mixture is shaken and left for 30 minutes at 40 °C. When tested with iodine solution, an orange-brown colour is observed. What are solutions X and Y? X Y A maltose altose amylase B maltose lipase C starch amylase D starch lipase 19 Which row correctly identifies the chemical elements found in proteins? carbon hydrogen oxygen nitrogen A key B = present C = absent D PhysicsAndMathsTutor.com 20 Nutrients are made up of smaller basic units. Nutrients can be identified by food tests. Which nutrient is a protein? nutrient smaller basic units food test A amino acids Benedict’s test B amino acids biuret test C sugars Benedict’s test D sugars biuret test 21 Which pair of substances is transported in the phloem? A amino acids and protein B amino acids and sucrose C protein and starch D starch and sucrose 22 Water is a good solvent. What does this mean? A It dissolves well in many other substances. B It flows easily through vessels. C It is permeable to gases. D Many substances dissolve well in it. 23 What does the digestion of starch produce? A fatty acids B glucose C mineral salts D water PhysicsAndMathsTutor.com 24 Which solutions are used for testing for protein, reducing sugar and starch? 25 The diagram shows part of a starch molecule. Which diagram shows this molecule after it has been completely digested? A B C D PhysicsAndMathsTutor.com 26 Four foods were tested for fat (using ethanol), protein (using the biuret test), reducing sugar (using Benedict’s solution), starch (using iodine solution). Which food contains protein and starch? colour of result of food test blue / black ilac purple / llilac orange bric-red / orange milky-white A key B = nutrient present C = nutrient absent D 27 The diagram shows a section through an eye. X Y What are structures X and Y? A organs in an organ system B organs in a tissue C organ systems in an organ D tissues in an organ PhysicsAndMathsTutor.com 28 Which elements do carbohydrates contain? A carbon, hydrogen and oxygen B carbon, hydrogen and sulphur C carbon, nitrogen and oxygen D carbon, nitrogen and sulphur PhysicsAndMathsTutor.com